1. Field of the Invention
This invention relates to construction elements, and more particularly to a panel of transparent material intended to form a construction element of the type having at least one flat bounding surface, the orientation of which determines a general plane of the panel, and at least one set of flat facets inclined relative to that general plane and disposed opposite the bounding surface in such a way that radiation issuing from a source outside the panel and passing through the transparent material undergoes at least in part the phenomenon of total reflection.
2. Description of the Prior Art
It has already been proposed to produce panels of this type for use as walls or partitions in dwellings, office buildings, or other premises to keep people inside from being blinded by direct insolation, while permitting as much irradiation as possible by means of the diffused sunlight. Thus, for example, U.S. Pat. No. 3,393,034 describes a design of this type in which the facing surfaces of two coupled plates of glass are provided with a configuration of facets forming horizontal ridges, constituting prisms which are nested into one another, one of the faces of each prism having an inclination which corresponds to the critical angle of the transparent material used, while the other facet is provided with an opaque coating which absorbs the radiation which has undergone total reflection. In this design, the radiation which undergoes total reflection on the facets of the prisms is therefore not returned toward the front side facing the source; moreover, the opaque surfaces naturally constitute obstacles to complete transparency of the panel. French Pat. Nos. 1,442,592 and 340,584 also describe designs of this type.